Clarification about the term "GPS Shutdown"

Discussion in 'General GPS Discussion' started by Sam Wormley, Dec 16, 2004.

  1. Sam Wormley

    Mxsmanic Guest

    Juergen Nieveler writes:

    Why? It can be placed just about anywhere.
    The more I look, the more spots I see.

    In any case, you can just design the system so that any loss of signal
    sets off an alarm.
    That's still not much of a restriction. Practically the entire ship
    above the waterline has a clear view of the sky.
    Lots of space available on both.
    Why not? And some spots are inaccessible to painters, anyway.
    If the system is designed correctly, any tampering with it will set off
    an alarm, so even if the crew is forced to walk the plank, it won't
    help.
    So you don't actually have any case histories? The _Pirates of the
    Caribbean_ ride at Disneyland probably isn't a good reference.
     
    Mxsmanic, Jan 4, 2005
  2. Sam Wormley

    Mxsmanic Guest

    You can connect the button to a small wireless local transmitter. Then
    the crew can't trace the button to the base unit.
    So what do you do once you detect that a ship is being hijacked?
     
    Mxsmanic, Jan 4, 2005
  3. Sam Wormley

    Mxsmanic Guest

    Ships don't move at the speed of sound. They can be spotted by
    satellites, too.
    These are very fanciful speculations. Ships don't move that fast. And
    it would take more than a few buckets of paint to repaint a ship. And
    repainting it doesn't hide its overall structure.
    Plus there's that big waterfall at the end.
     
    Mxsmanic, Jan 4, 2005
  4. Sam Wormley

    Mxsmanic Guest

    Your point makes little difference. You simply design the system such
    that any loss of signal triggers the alarm.
    As a rule, smart people are not dishonest, because they see the
    long-term advantages of honesty for themselves and for society.
    This sounds like pure conjecture.

    It's easy to hide a small transmitter on a large ship. The crew doesn't
    have to know where it is. And even if they know and Captain Hook
    disables the transmitter, doing this alerts the owner to his presence.
     
    Mxsmanic, Jan 4, 2005
  5. Sam Wormley

    Dave Baker Guest

    We just inform the owner immediately - it's up to them what they do next,
    though we can supply the data in real-time to the relevant authorities.

    In the case of SSAS (Ship Security Alert System) which is fitted to most
    vessels (over 500 tons) by now, there is a set procedure that must be
    followed - basically reporting to the maritime authorities in the country of
    vessel flag, the destination country & the country in which the alert
    occurred.

    So, if a Panama flagged vessel got hijacked in Indonesian waters while
    enroute to Singapore, maritime authorities in all 3 countries would be
    notified.

    Of course there are lots of vessels that are not legally required to have
    SSAS installed but nevertheless have similar systems. If one of these are
    triggered then the owner will do whatever they feel best.

    Dave

    The email address used for sending these postings is not valid.
    All replies to the group please.
     
    Dave Baker, Jan 4, 2005
  6. Ships move relatively fast nowadays, and the ocean is huge. And the
    units that would do the tracking don't move at the speed of sound
    either, they'd be frigates or destroyers, doing maybe 30 knots.

    Tracking ships via satellite images isn't THAT easy, even if you had
    access to military satellites (which I'd rather doubt, unless the ship
    is US-owned), and ships can be camouflaged rather easy by giving them a
    paint job - paint over the name, new markings on the deckhouse, and
    you'll have to come close to check wether it's the ship you're looking
    for.
    You don't need to repaint the hull. Just paint a new name on it and
    change some details of the rest of the ship, and she'll look like a
    totally different ship. The overall structure doesn't really help all
    that much, ships of the same type look quite similar. Of course that
    won't help once the ship gets boarded for inspection, but it would help
    fool patrol plane crews and keep the inspection teams away.

    Juergen Nieveler
     
    Juergen Nieveler, Jan 4, 2005
  7. Being dishonest and not getting caught has rather more long term
    advantages.
    The transmitter location would have to follow some requirements, which
    severly limits the choice of spots. And unless there are anti-piracy-
    patrols, alerting the owner will only allow him to call his insurance
    company faster.

    Even the best tracking system is worthless until you find a way to use
    the information it provides.


    Juergen Nieveler
     
    Juergen Nieveler, Jan 4, 2005
  8. How widespread is use of these systems? Once all ships are equipped
    with them, pirates will be forced to adapt and react...
    If the crew don't know where the antenna is, how do you stop them from
    painting it accidentally? It would have to be marked as "Do not paint"-
    spot, just like all other antennas, wouldn't it?
    Of course.
    And then what? That's the most interesting question - if the signal is
    lost, are there any naval forces nearby that can be asked to
    investigate?

    I agree that a tracking system that lets you know immediately that your
    vessel is under attack is valuable - but only if you can actually do
    something about the attack.
    Indeed, that's what I see as the worst problem. If there was a military
    alliance in that region (SEATO never really got off the ground...),
    things would be easier. Last I've heard is that the US is backing a
    "Regional Maritime Security Initiative", but I don't really think
    Indonesia is going to buy into this (as it's a mostly Islamic country).
    Add to that the fact that in SE Asia there are some troublespots where
    the local governments don't have control and the rebels are even less
    US-friendly (Aceh on Sumatra, for example), and the corruption problems
    in the region (officials won't do much to stop the pirates if they
    receive enough money...).

    Juergen Nieveler
     
    Juergen Nieveler, Jan 4, 2005
  9. Not THAT many, actually
    I can see a lot of spots that AREN'T available.
    Of course, and that would be done anyway. The question then is: How
    fast can naval units reach the spot where you lost contact.
    Let's take a container ship as an example. Most of the deckspace is
    used for containers. Between the containers is no space, and reception
    would be poor anyway. Outside the containers are the walkways - also
    not a good spot for an antenna, people would keep treading on it. The
    sides of the ship would be ideal - but then you'd need more than one
    antenna, otherwise line-of-sight to the satellite could be masked by
    the ship. The bow would be a nice place, but as at least part of the
    system would be on the bridge, it would mean that you'd have to pull
    wires all through the ship. Easily done when the ship is built, but not
    as easily done on older ships. Placing it near the radar or radio
    antennas might cause problems with interference, especially since a
    small antenna will have less reserves to "burn through" such
    interferences. It would have to be a spot that doesn't get accessed by
    the crew too much, because the crew don't know where it is and could
    accidentally paint over it, reducing its effectiveness.

    The best spot for the antenna would be on the mast, somewhere above the
    radar antenna - but of course that would be the first place where
    anyone would go looking for it.
    Nope. The containers take up most of the space on a container ship.
    If you paint an antenna, the paint will severly weaken the signal. A
    small antenna doesn't have that much power to begin with... painting
    over it with normal paint would render it useless.
    And then what? You know your ship is lost, but unless any naval units
    can be raised the ship will stay lost.


    Juergen Nieveler
     
    Juergen Nieveler, Jan 4, 2005
  10. The areas are known, but patroling an area like the Malacca Straits
    isn't THAT easy, both politically and technically. Most notably, the
    countries in that region won't really allow foreign navy ships into
    their regional waters but lack a big enough navy to patrol these waters
    alone. Add to that some government officials who turn a blind eye in
    return for some donations... if it was that easy to stop piracy, there
    wouldn't be a need for tracking systems and electric fences on ships.


    Juergen Nieveler
     
    Juergen Nieveler, Jan 4, 2005
  11. Sam Wormley

    JGS Guest

    Dave

    Thank you very much for your insightful and informative posts on this
    subject. It really opens up my mind to what is happening in the world
    outside my own sometimes small sphere in which I live, work, and think.

    Very thought provoking and quite enlightening.

    Thanks for sharing your real world experience with me. I have really enjoyed
    it and learned a lot of new things in the process.

    Best wishes and good luck to you.

    Regards
    JGS
     
    JGS, Jan 4, 2005
  12. Jürgen,

    I would guess the usual problem is collusion between the pirates
    and the authorities. This is common in developing countries.

    The pirate will call his brother, who works for the waterway
    authorities, and the latter will mislead any rescue activities.

    Hans-Georg
     
    Hans-Georg Michna, Jan 4, 2005
  13. Sam Wormley

    Dave Baker Guest

    I can't find the picture on the web at the moment, but one company has a nice
    Orbcomm tracking unit that fits into the ribs on top of each container. Nice
    unit - onboard batteries last 6 months or a year.

    I've been to a trade show where a South African company introduced a system
    where each individual container is fitted with a satellite tracking system &
    also a local wireless network. Therefore, a container on the bottom of the
    stack can radio out to the network that it has lost refridgeration, and the
    top container can tx that by satellite. I'd hate to be paying for that, but
    this is the way the industry is heading - to stop this system working you are
    going to have to wreck every container as they are all individually battery
    powered, and wrecking the first one breaks the data link, making the rest
    "more suspicious".

    Dave

    The email address used for sending these postings is not valid.
    All replies to the group please.
     
    Dave Baker, Jan 5, 2005
  14. Sam Wormley

    Dave Baker Guest

    SSAS is required by IMO under SOLAS Convention Chapter XI-2/6 on all ships
    over 500 tons meeting certain requirements, though some types still have
    another year or so before being compulsory:
    http://www.us.weathernews.com/marine/asap.htm
    (grey panel on right side of web page gives exact requirements)

    As I mentioned before, many non-SOLAS boats are fitting themselves with
    similar (& often more covert) systems anyway. SSAS is anti-terrorism, while
    the main problem around Asia is piracy. Slightly different requirements, as
    we are dealing with different levels of sophistication of the enemy.

    Pirates are usually villagers or fishermen & not technically adept at all - 9
    times out of 10 they will not touch anything on board, and 1 time out of 10
    they will slash any wires they can find & disable all power they can find.
    Never heard of a tracking system being disabled, and in fact turning off
    external power enables a transmission saying "I've lost power".

    Terrorists are a different kettle of fish. They are pretty likely to study
    their target in advance & are harder to combat. The SSAS is supposed to
    combat against this sort of thing, but if it doesn't, blame the IMO, not me!
    :) I design anti-piracy units myself, and would have done the SSAS
    differently.
    Might I suggest you don't spend much time around real working ships? :)
    Crews only paint what they have to, and don't paint anything that isn't metal
    - standard practice. Out of hundreds of vessels I haven't seen any of them
    with painted antennas on our regular inspections.

    It would have to be marked as "Do not paint"-
    Take a look for yourself:

    http://www.satamatics.com/content/news/22_apr_2004_ocean_alert_for_Posidonia.htm
    http://www.skywave.com/products/DMR-200-D.html

    We don't add any sticker on afterwards.
    Not usually, but there are often other boats that can be used to help. First
    step is to contact the boat itself & make sure all is ok, in a manner which
    will not alert any hijackers - I'll leave this to your imagination. If
    contact can't be raised then the situation is more worrying, and further
    steps are taken.
    True, but we are only one link in the chain.
    Well, there is an alliance, just that the USA isn't invited. :)
    Really, only India & Indonesia are the problem areas around here, with
    Nigeria over the other side of the world. Indonesia is a poor country with a
    damn lot of islands, and not much of a Navy. Maybe the USA could donate a few
    hundred patrol boats instead of wanting to stomp around where they aren't
    welcome? :)

    Dave

    The email address used for sending these postings is not valid.
    All replies to the group please.
     
    Dave Baker, Jan 5, 2005
  15. Sam Wormley

    kashe Guest


    Look around, idiot.
     
    kashe, Jan 5, 2005
  16. Sam Wormley

    kashe Guest

    I'm honored. I'd not want to have my postings read by mindless
    assholes like you.
     
    kashe, Jan 5, 2005
  17. Sam Wormley

    kashe Guest

    He didn't. And he arrived at the correct destination.
     
    kashe, Jan 5, 2005
  18. Sam Wormley

    Mxsmanic Guest

    As a rule, smart people are not dishonest, because they see the
    long-term advantages of honesty for themselves and for society. Stupid
    people are not good at understanding and seeing long-term consequences,
    and so they will assume that dishonesty is best.

    The reason society as a whole tends to favor honesty is that it is
    largely run by the more intelligent segments of the population, and
    these intelligent people see the long-term advantages of honesty.
     
    Mxsmanic, Jan 5, 2005
  19. Sam Wormley

    Mxsmanic Guest

    There is a large amount of room for error in transatlantic crossings.
     
    Mxsmanic, Jan 5, 2005
  20. Sam Wormley

    kashe Guest


    Sure, asshole; in your fantasy world, anything is possible.

    You're the one insisting GPS units which require power are
    superior to map and compass which require no fuel of any kind.
     
    kashe, Jan 5, 2005
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